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Geomaterials 2022年第4期12卷 70-92页

作者： Laurence Boisvert Claude Bazin Josiane Caron françois lavoie Department of Mining Metallurgical and Material Engineering Laval University Quebec City Canada Quebec Iron Ore Fermont Canada

For complex orebodies in which the valuable metal is carried by several minerals that respond differently to the concentration process, an ore block model should not be characterized solely with elemental assays, as this information is not sufficient to anticipate the mill performances. Data from an iron ore concentrator is used to demonstrate the idea. A method is then proposed to estimate the mineral contents of ore samples from elemental assays. The method can readily be extended to combine the estimation of the mineral contents in the feed of the mill with an estimation of the recovery of these minerals into the products of the concentrator. These mineral recoveries can subsequently be incorporated into a block model to predict the concentrator response to the processing of an ore block.

关键词： Block Model Estimation Geometallurgy Iron Ore Concentrator Mill Performance Mineral Content Modal

A public health mission in Canada in response to the coronavirus disease 2019(COVID-19)pandemic

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Global Health Journal 2022年第4期6卷 231-236页

作者： Marie lavoie Department of Economics the Glendon School of Public and International AffairsGlendon CampusYork UniversityTorontoOntario M4N 3M6Canada

Many governments in the world reacted to the coronavirus disease 2019 pandemic by swiftly offering stimulus packages to their *** public unpreparedness was dramatic,it was not unexpected:many alarms had been *** by the federal and various provincial governments of Canada in core sectors predis-posed the country to the current situation and weakened its capacity to respond *** paper reviews the cumulative effects of these strategic orientations:a deficient investment strategy in fundamental science;dis-connect between laboratory work and the country's capacity to produce vaccines and antiviral drugs;the priority of cost efficiency that led to overwhelming dependency on foreign production of medical supplies;and dramatic spending cuts in public *** will discuss a Mission strategy to exit the crisis that takes a long-term perspec-tive,in which public interest and public health,combined with a strong State leadership,stimulate innovation and collaboration between national and international actors.

关键词： Fundamental research Innovation Mission Public health Pandemic

Effect of temperature in the conversion of methanol to olefins （MTO） using an extruded SAPO-34 catalyst

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Frontiers of Chemical Science and Engineering 2018年第2期12卷 226-238页

作者： Ignacio Jorge Castellanos-Beltran Gnouyaro Palla Assima Jean-Michel lavoie Universit6 de Sherbrooke Chaire de Recherche Industrielle sur l'Ethanol Cellulosique et les Biocommodities (CRIEC-B) Sherbrooke QC Canada J1L 2Y4

The methanol-to-olefin （MTO） reaction was investigated in a bench-scale, fixed-bed reactor using an extruded catalyst composed of a commercial SAPO-34 （65 weight percentage, wt-%） embedded in an amorphous SiO2 matrix （35 wt-%）. The texture properties, acidity and crystal structure of the pure SAPO-34 and its extruded form （E-SAPO-34） were analyzed and the results indicated that the extrusion step did not affect the properties of the catalyst. Subsequently, E-SAPO-34 was tested in a temperature range between 300 and 500 ~C, using an aqueous methanol mixture （80 wt-% water content） fed at a weight hour space velocity （WHSV） of 1.21 h-1. At 300 ~C, a low conversion was observed combined with the catalyst deactivation, which was ascribed to oligomeriza-tion and condensation reactions. The coke analysis showed the presence of diamandoid hydrocarbons, which are known to be inactive molecules in the MTO process. At higher temperatures, a quasi-steady state was reached during a 6 h reaction where the optimal temperature was identified at 450℃, which incidentally led to the lowest coke deposition combined with the highest H/C ratio. Above 450℃, surges of ethylene and methane were associated to a combination of H-transfer and protolytic cracking reactions. Finally, the present work underscored the convenience of the extrusion technique for testing catalysts at simulated scale-up conditions.

关键词： MTO SAPO-34 temperature extrusion coke light alkanes

Predicting plant invasiveness from native range size: clues from the Kashmir Himalaya

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Journal of Plant Ecology 2012年第2期5卷 167-173页

作者： Manzoor A.Shah Zafar A.Reshi Claude lavoie Department of Botany University of KashmirSrinagar-190006Jammu and KashmirIndia Ecole superieure d’amenagement du territoire et de developpement regional Universite LavalQuebec CityQuebec G1V 0A6Canada

Aims In view of the growing interest in modelling the potential spread of invasive species,prediction of plant invasiveness on the basis of native range size holds considerable *** objective was to use a simple model to evaluate whether a wider native range predisposes plant species to become invasive in non-native regions and to easily identify potential invaders on this *** Kashmir Himalayan alien flora,of which a large proportion is native to Europe,was used to test this *** The Kashmir Himalayan alien flora comprises 436 species of vascular plants at different stages of *** focussed on plant species at two critical invasion stages(sensu Colautti and MacIsaac 2004),*** II(species that are just at the earliest phase of introduction)and Stage V(species that are widespread and dominant in the invaded region and are thus considered invasive).We used the territorial distribution in Europe(number of countries)as a surrogate for the native range size of plants of European *** Findings Using a subset of 88 species,for which information on the native European range was available,we showed that a large proportion(68%)of Stage II species growing in the Kashmir Valley had a relatively restricted European range(present in20 countries).We consequently hypothesized that 14 Kashmir Himalayan Stage II species of European origin that are distributed in>20 European countries are at risk of becoming future invaders in *** the other hand,those Kashmir Himalayan Stage II species of European origin distributed in<20 European countries are less likely to become *** this analysis is quite simple,the data suggest that a wider native range is a good predictor of plant invasiveness and could be used as a simple and low-cost early warning tool in predicting potential invasive species.

关键词： Colautti and MacIsaac model early warning system Kashmir Himalaya native range plant invasion prediction and management

Harnessing the potential of additive manufacturing technologies:Challenges and opportunities for entrepreneurial strategies

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International Journal of Innovation Studies 2018年第4期2卷 123-136页

作者： Marie lavoie James L.Addis York University/Glendon College-Economics Department and Glendon School of Public and International Affairs 2275 Bayview AvenueTorontoOntarioM4N3M6Canada York University/Glendon College-Economics Department 2275 Bayview AvenueTorontoOntarioM4N3M6Canada

Additive manufacturing(AM),a revolutionary production technique that will make many previously inconceivable innovations a reality,is transforming the manufacturing *** technologies behind AM have a generic character and possess immense and transformative potential that will be felt across different sectors of the *** paper studies how entrepreneurs can access,exploit,and diffuse this new disruptive knowledge,as well as the potential challenges that lie ***,we examine the magnitude of the knowledge pool created by the Top 10 countries in AM research from 2011 to 2016;specifically,we determine the leading countries,the pattern of organizational and international collaborations,leading disciplines contributing to AM,and the pattern in authors'*** find that the US is clearly the dominant country,while China witnessed a notable acceleration in AM research between 2014 and 2016;we also show that universities are the predominant actor in codified AM knowledge *** this information,we paint a vivid picture of the technological and market opportunities for entrepreneurs and identify the gaps in the current knowledge production environment;we find that the challenges currently faced by entrepreneurs could be overcome through academic entrepreneurship,collective entrepreneurship,and the actions of an entrepreneurial state.

关键词： Additive manufacturing Knowledge pool Entrepreneurship Innovation systems Innovation policy Evolutionary economics

Human viral pathogens are pervasive in wastewater treatment center aerosols

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Journal of Environmental Sciences 2018年第5期30卷 45-53页

作者： Evelyne Brisebois Marc Veillette Vanessa Dion-Dupont Jacques lavoie Jacques Corbeil AlexANDer Culley Caroline Duchaine Universite Laval Pavillon Alexandre Vachon1045ave de la MedecineQuebecQC GIVOA6Canada CRIUCPQ 2725 Chemin Sainte-FoyQuebecQC GIV 4G5Canada IRSST 505 Boulevard de Maisonneuve OMontréalQCH3A 3C2Canada CRCHU 2705 Boulevard LaurierRC-709QuébecQCG1V 4G2Canada

Wastewater treatment center（WTC） workers may be vulnerable to diseases caused by viruses, such as the common cold, influenza and gastro-intestinal infections. Although there is a substantial body of literature characterizing the microbial community found in wastewater, only a few studies have characterized the viral component of WTC aerosols,despite the fact that most diseases affecting WTC workers are of viral origin and that some of these viruses are transmitted through the air. In this study, we evaluated in four WTCs the presence of 11 viral pathogens of particular concern in this milieu and used a metagenomic approach to characterize the total viral community in the air of one of those WTCs. The presence of viruses in aerosols in different locations of individual WTCs was evaluated and the results obtained with four commonly used air samplers were *** detected four of the eleven viruses tested, including human adenovirus（h Ad V）,rotavirus, hepatitis A virus（HAV） and Herpes Simplex virus type 1（HSV1）. The results of the metagenomic assay uncovered very few viral RNA sequences in WTC aerosols, however sequences from human DNA viruses were in much greater relative abundance.

关键词： Airborne viruses Air sampling Wastewater treatment plants Viral metagenomics

Interleukin(IL)-4 Induces Production of the Lung Cytokine-induced Neutrophil Chemoattractants(CINCs)and Intercellular Adhesion Molecule(ICAM)-1 in Rats

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Interleukin(IL)-4 Induces Production of the Lung Cytokine-in...

中华医学会呼吸病学年会——2011（第十二次全国呼吸病学学术会议）

作者： Jean-Pierre lavoie Department of Clinical Sciences Faculty of Veterinary MedicineUniversite de Montreal3200 SicotteSaint-HyacintheQuebecCanadaJ2S 7C6

Interleukin(IL)-4 plays a critical role in allergic lung disease,but its contribution to airway neutrophilia remains *** studies provided evidence that IL-4 caused neutrophils infiltrating by increasing expression CXCL-8 and intercellular adhesion molecule(ICAM)-1 in vitro. However,its contribution to airway neutrophilia in vivo is poorly *** we hypothesized

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燃料—空气炸药武器及效能

飞航导弹 1990年第7期 10-13,24页

作者： Louis lavoie 李峰新

本文首先介绍了燃料—空气炸药(FAE)的基本概念,对FAE的两个独特特性——它本身不带或携带很少的氧,具有较高的质量利用率;它是面爆炸,比常规高能炸药的点爆炸产生更大的冲量——进行了分析研究;其次,在上述基础上讨论了FAE的武器化问题... 详细信息

本文首先介绍了燃料—空气炸药(FAE)的基本概念,对FAE的两个独特特性——它本身不带或携带很少的氧,具有较高的质量利用率;它是面爆炸,比常规高能炸药的点爆炸产生更大的冲量——进行了分析研究;其次,在上述基础上讨论了FAE的武器化问题,对FAE的战术运用进行了分析讨论并提出了一些建议;最后指出FAE是攻击软目标的理想武器并是来来战争中最常选用的武器。

关键词：空气炸药燃料武器

Receptive Anal Intercourse and HIV Infection

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World Journal of AIDS 2017年第4期7卷 269-278页

作者： Gilbert R. lavoie John F. Fisher Medical Institute for Sexual Health Austin Texas USA Department of Infectious Disease Medical College of Georgia Augusta University Augusta Georgia USA

Objective: Inform the public that receptive anal intercourse (RAI) is a key transmission route of the human immunodeficiency virus (HIV) epidemic in the United States. Method: The role of receptive anal intercourse (RAI) in this epidemic will be examined using the following approach: 1) Risk comparison of HIV transmission via RAI to the other major routes of transmission. 2) HIV transmission risks of RAI using some of the present risk reduction techniques. 3) HIV infection via anal intercourse among male youth. 4) HIV infection via anal intercourse among women. Results: Of the major transmission routes of HIV, receptive anal intercourse has the highest transmission risk for acquiring HIV infection. RAI is 2 times the risk of needle-sharing during injection drug use (IDU) and 17 times the risk of receptive vaginal intercourse. The estimated per act probability of acquiring HIV from an infected source by the exposure route of RAI is high in most circumstances: 1) Condoms alone only partially reduce the high risk of RAI. With the addition of pre-exposure prophylaxis (PrEP), the risk is further reduced. 2) When one or both partners are infected with a sexually transmitted disease (STD), even with condom use, the risks are very high. With the addition of PrEP the risks are reduced, but RAI still carries significant risks. 3) With exposure to acute HIV (high viral load) the risks of RAI are very high and remain significant even with condom use and PrEP. Anal intercourse often begins in adolescence;both genders are at risk. Conclusion: Public knowledge of the high transmission risks of receptive anal intercourse may likely result in a downward trend of new HIV infections and contribute to ending the epidemic.

关键词： HIV Transmission Risk Receptive Anal Intercourse Anal Intercourse STD Condom Use

Dynamics of hepatic and intestinal cholesterol and bile acid pathways: The impact of the animal model of estrogen deficiency and exercise training

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World Journal of Hepatology 2016年第23期8卷 961-975页

作者： Jean-Marc lavoie Department of Kinesiology University of Montreal

Plasma cholesterol level is determined by a complex dynamics that involves transport lipoproteins which levels are tightly dependent on how the liver and the intestine regulate cholesterol and biliary acid metabolism. Regulation of cholesterol and biliary acids by the liver and the intestine is in turn coupled to a large array of enzymes and transporters that largely influence the inflow and the outflow of cholesterol and biliary acids through these organs. The activity of the key regulators of cholesterol and biliary acids may be influenced by several external factors such as pharmacological drugs and the nutritional status. In recent years, more information has been gathered about the impact of estrogens on regulation of cholesterol in the body. Exposure to high levels of estrogens has been reported to promote cholesterol gallstone formation and women are twice as likely as men to develop cholesterol gallstones. The impact of estrogen withdrawal, such as experienced by menopausal women, is therefore of importance and more information on how the absence of estrogens influence cholesterol regulation is started to come out, especially through the use of animal models. An interesting alternative to metabolic deterioration due to estrogen deficiency is exercise training. The present review is intended to summarize the present information that links key regulators of cholesterol and biliary acid pathways in liver and intestine to the absence of estrogens in an animal model and to discuss the potential role of exercise training as an alternative.

关键词： PSCK9 Low-density Lipoprotein receptor Very low-density Lipoprotein Sterol regulatory element binding proteins Ovariectomy High-density Lipoprotein Lipoproteins